My two year old filly is very easy to handle and to work with. Until you try to take the other horse out of the pasture. As soon as I open the gate she is barging her way through. I have tried many different things and obviously none of them have worked. Can anyone suggest something. This is really starting to tick me off!!

The root of this problem, and almost all bad ground habits is lack of respect for you. You are a "flea on the butt of an elephant" to her. I'll bet she also steps on you when you lead her. I can guarantee, if the boss mare was standing in the gate, that filly would never charge the gate. Why? Because she'd get the begeebers kicked out of her. The boss mare has an acceptable amount of "space" around her that is not encroached upon. You need to recapture that "space" for yourself.

If you're not comfortable, scared, not strong enough or not quick enough, take the horse to a trainer. You'll end up with a well adjusted, safe member of the family, that understands her place. If you fail in your training, the horse gets worse and will take harsher techniques to cure.

Put a halter on her with a chain over the nose. Open the gate, but don't stand in front of her. When she charges, yell whoa and snap the chain as hard as required to get her attention. Make her stand still and repeat, allowing her to only take a step at a time. Pretty soon she won't move until you tell her to and she'll be tip-toeing out of the pasture. This is the first step. Now that you have her attention and she is gaining respect for you, go to the next step - carry a big stick. Put her in a round pen and get her trotting or loping. Stand in front of her with a whip and snap it, yell, wave your hands, etc. to get her to go around. This is dangerous. It's a game of chicken. A really aggressive horse will run you over. The horse has to understand that you have an invisible "space" around you that cannot be invaded, for any reason, at any time, no excuses. When leading her, carry a crop and poke her in the shoulder, or in extreme cases, hit her if she enters your "space." My "space" is arm's length. I don't ever want to have a horse closer than reaching out and touching them with a straight arm. Any more and it's hard to lead them. Any less and they walk on you. Don't make allowances or excuses. If a purple alien with sparks shooting out of it's eyes, lands on the horse's back, grabs both ears and ties them in a knot, that horse had better find another place to go other than my "space."

Now back to the pasture, carry the crop or whip with you. Many horses start crowding the gate before it's opened. Before you open the gate make sure the horse is giving you room. Open the gate, blocking it with your body, and make menacing gestures and snap the whip. Do it before they ever get near the gate. If you've done your homework, the filly won't dare run you over. If she does, go back to leading and the roundpen and start over.

These methods may seem harsh, but a horse that runs over you is dangerous. If you think this is bad, watch a boss mare kick the begeebers out of a smart-alec two year old. Once again, get a triner if you're not comfortable with any step. My wife handles all our young horses, until they begin their terrible twos. When they get her number, she hands them over to me to teach manners. All her years around horses and she still can't handle a horse that steps on her.

I want to be able to sit on a horse, turn around and talk to someone behind or to the side, trim a branch off the trail, or get a beer out of the pack, without the horse taking off. As long as my reins are dropped, I don't want them moving. Once I pick up the reins, they should know it's time to get busy.
Is the mare extremely sensitive to leg and seat cues? Maybe she is just trying to please, thinking that everytime you move, you want to do something and go somewhere. If that is the case, you need to desensitize her. Aim her into a corner of the riding arena, drop the reins but keep hold of them, and brush your legs on her side and shift your weight. When she moves, she'll try to get out of the corner. Insead of bumping her in the mouth, steer her back into the corner. Pretty soon she'll understand that unless you pick up a rein, you don't want to go anywhere. Once she'll stand still in a corner, with you moving and bumping her side with your legs, begin picking up the reins and asking her to move. Then put her back in the corner, drop the reins and bump her with your legs. Pretty soon she will realize the difference between incidental contact and picking up the reins to work. Once she has that, move away from the corner a little at a time, until she'll stand anywhere unless you pick up the reins.
Susan is right. Not much you can do for a year or so. Stopping while leading is a problem. I never belive people that say their horse is halter broke until I lead them myself.
I can just hear the horses in the pasture talking about how they their human is halter broke. "You know I can go wherever I want to go, stop whenever I want to stop, jump on top of them if I act real scared, dance around when they want to stop and all the time they're fedding me treats and telling me what a good boy I am." I don't consider a horse halter broke until they: walk quietly at my shoulder, without any pulling on the halter; stop when I stop, without touching the halter; trot out at my shoulder, without pulling on the halter; walk through a puddle, even if I'm walking on dry ground, without stepping all over me; and stop and stand quietly whenever I want to stop. If you ever have to stop and wait until a horse decides to walk off, and tug on the lead, I don't consider them halter broke. I love to see a real horseman leading a stallion through a crowded horseshow, and the stallion is leading quietly, completely attentive to his surroundings, but knowing that he'd better not whimper or break his stride. That's a halter broke horse.
Work on him doing exactly what you want him to do, when you want him to do it, not when he decides to. Just remember to keep the lessons short, praise only if he truly does something right, and heap on the praise if it's deserved.

Pullers can rarely ever be completley cured but this will do it for a time and each time it will get easier.
Now for the disclaimers: Do not try this if you are not an experienced horse person. Do not try this if you are frightened of a horse thrashing around. Do not try this alone - always have another person nearby. Always keep something handy to cut the rope if something unexpected happens.
Tie a rope at wither level to a strong tree, telephone pole, or post. Make sure whatever you tie to is strong enough to not come out of the ground or break. Try to find a place that has soft footing like a round pen. Make sure nothing is within reach that could hurt the horse. Don't do this near a fence that they can get over. Make sure you have room to escape. Run a sturdy cotton rope through the halter, between the legs, over the back and tie a slip bowline knot back under the belly. Some run a lariat around the barrel and then through the halter, but the lariat will sometimes mark the horse. You want a soft cotton rope, strong enough to hold a horse in all its furry without breaking, tied around the barrel with a slip knot that will tighten with pressure and loosen when pressure is released.
Tie the end of the rope to the tree with about 6-10 feet between the tree and horse. Pullers are usually spooky horses, so shake a feed sack, rattle rocks in a can, on do whatever sets your horse off. STAND BACK. The horse will come tight to the end of the rope and begin pulling. The rope will tighten around the barrel and the horse will pull harder. The horse will usually rear up and then leap forward out of the rear. That's the dangerous time. The horse will shake its head, run back and forth and generally thrash about until it finds out it can't get loose. Some will throw themselves on the ground. Some will pull back steadily, until it looks like they'll pass out. Try whatever you can to set the horse off. Some horses only require standing there a few minutes until they try it again.
You know they're finished when the horse will do anything to not come tight to the rope. They'll begin circling the tree, trying to not tighten the rope. Some horses get in one pull. Confirmed pullers will take an hour or more. Try to do this when it's cool so the horse doesn't overheat.
Make sure the rope and halter are strong enough. If either break you're worse off than when you started. Don't give in. First one to quit loses. Expect a few rub marks in the girth area no matter what you do, so don't do this before a trail ride or show.
Sorry. but you've tried everything else. I never liked the inner tube because it breaks and then you're worse off. The reason this works is that the horse punishes itself and learns that the most comfortable place is with a loose lead. This is drastic, but a runaway horse is dangerous to everyone around them. The belly roped horse is only dangerous to itself for a while, and then becomes safe again.
Please be careful.

As an owner of Arabs, I have much experience with spooky horses. Usually the smarter horses are the spookiest. Often the rider sets the horse off. Sit on a spooky horse and jerk in the saddle quickly. The horse will spook nine times out of ten. When you spook, the horse thinks there is something there, even if there isn't. I found that the more I relaxed, the less spooky the horse became.
That helps, but doesn't completely cure the problem. A good old sacking out usually improves things. Why we got away from sacking out I'll never know. It used to be standard with all horses. I sack out differently than most. Some tie hard a fast and let the horse pull against the halter and lead. This seems to punish the horse instead of training it. Others, like John Lyons, chase the horse until they stop and face you. I firmly believe that the John Lyons method teaches a horse to spook. What are you teaching them? If I'm scared, run away until I'm not scared anymore. That's not what I want to ride. I fall somewhere in the middle. I hold a soft lead rope in one hand and the sack in the other and chase the horse with it until they stand still. If the horse isn't really halter broke you have to "double" them first, but that's another lesson. I don't ever tiptoe around a horse. I believe that the more you tiptoe, the more you have to tiptoe. Run right up to the horse on the lead rope. Turn around and yell at them. Wave your arms like a madman. They'll jump, and some will try to run away, but just let them circle around on the lead rope till they settle. After they stop bolting with this stimuli, find something else they're afraid of. Put a feed sack or plastic bag on a lunge whip and shake it all around the horse. This teaches the horse to turn and face his fears instead of running. You'll soon have a horse that will stop and squat when frightened, instead of bolting. Word of warning: Make sure this horse respects your space before you try this, or they'll run you over. Be careful, as any horse training can be dangerous.
TimC